Throttle Position Switch: Description and Operation

Throttle Position Switch:

FOR FUEL INJECTION ECU:
The ECU supplies a voltage (at two terminals) to the throttle position sensor. When the throttle valve is closed (idle position) or in the full load position, the sensor grounds the ECU, allowing the current to flow from one of the two terminals. This will indicate the throttle position to the ECU. The throttle position sensor is located on the throttle housing.

FOR IGNITION ECU:
The fuel injection ECU supplies a voltage (at two terminals) via the ignition ECU to the throttle position sensor. When the throttle valve is closed (idle position) the sensor grounds the ECU, allowing the current to flow from the terminal. This will indicate the throttle position to the ignition ECU. The throttle position sensor is located on the throttle housing.